Clethra alnifolia ( Summer Sweet Clethra )

Characteristics

Cultivar:	Pink Spires
Family:	Clethraceae
Size:	Height: 5 ft. to 8 ft. Width: 5 ft. to 8 ft.
Plant Category:	climbers, shrubs,
Plant Characteristics:	low maintenance, spreading,
Foliage Characteristics:	deciduous,
Foliage Color:	dark green, green,
Flower Characteristics:	fragrant, long lasting, single,
Flower Color:	pinks, reds, whites,
Tolerances:	slope,

Requirements

Bloomtime Range:	Late Summer to Early Fall
USDA Hardiness Zone:	5 to 8
AHS Heat Zone:	5 to 9
Light Range:	Dappled to Part Sun
pH Range:	4.5 to 6.5
Soil Range:	Sandy Loam to Some Clay
Water Range:	Normal to Moist

Plant Care

Fertilizing

How-to : Fertilization for Established Plants

Established plants can benefit from fertilization. Take a visual inventory of your landscape. Trees need to be fertilized every few years. Shrubs and other plants in the landscape can be fertilized yearly. A soil test can determine existing nutrient levels in the soil. If one or more nutrients is low, a specific instead of an all-purpose fertilizer may be required. Fertilizers that are high in N, nitrogen, will promote green leafy growth. Excess nitrogen in the soil can cause excessive vegetative growth on plants at the expense of flower bud development. It is best to avoid fertilizing late in the growing season. Applications made at that time can force lush, vegetative growth that will not have a chance to harden off before the onset of cold weather.

Light

Conditions : Partial Shade

Partial Shade is defined as filtered light found beneath trees with high limbs. Partial shade usually offers some protection from direct afternoon sun.

Conditions : Dappled Light

Dappled Light refers to a dappled pattern of light created on the ground, as cast by light passing through high tree branches. This is the middle ground, not considered shady, but not sunny either. Dappled remains constant throughout the day.

Watering

Conditions : Moist and Well Drained

Moist and well drained means exactly what it sounds like. Soil is moist without being soggy because the texture of the soil allows excess moisture to drain away. Most plants like about 1 inch of water per week. Amending your soil with compost will help improve texture and water holding or draining capacity. A 3 inch layer of mulch will help to maintain soil moisture and studies have shown that mulched plants grow faster than non-mulched plants.

Planting

How-to : Pruning Flowering Shrubs

It is necessary to prune your deciduous flowering shrub for two reasons: 1. By removing old, damaged or dead wood, you increase air flow, yielding in less disease. 2. You rejuvenate new growth which increases flower production.

Pruning deciduous shrubs can be divided into 4 groups: Those that require minimal pruning (take out only dead, diseased, damaged, or crossed branches, can be done in early spring.); spring pruning (encourages vigorous, new growth which produces summer flowers - in other words, flowers appear on new wood); summer pruning after flower (after flowering, cut back shoots, and take out some of the old growth, down to the ground); suckering habit pruning (flowers appear on wood from previous year. Cut back flowered stems by 1/2, to strong growing new shoots and remove 1/2 of the flowered stems a couple of inches from the ground) Always remove dead, damaged or diseased wood first, no matter what type of pruning you are doing.

Examples: Minimal: Amelanchier, Aronia, Chimonanthus, Clethra, Cornus alternifolia, Daphne, Fothergilla, Hamamelis, Poncirus, Viburnum. Spring: Abelia, Buddleia, Datura, Fuchsia, Hibiscus, Hypericum, Perovskia, Spirea douglasii/japonica, Tamarix. Summer after flower: Buddleia alternifolia, Calycanthus, Chaenomeles, Corylus, Cotoneaster, Deutzia, Forsythia, Magnolia x soulangeana/stellata, Philadelphus, Rhododendron sp., Ribes, Spirea x arguta/prunifolia/thunbergii, Syringa, Weigela. Suckering: Kerria

How-to : Planting Shrubs

Dig a hole twice the size of the root ball and deep enough to plant at the same level the shrub was in the container. If soil is poor, dig hole even wider and fill with a mixture half original soil and half compost or soil amendment.

Carefully remove shrub from container and gently separate roots. Position in center of hole, best side facing forward. Fill in with original soil or an amended mixture if needed as described above. For larger shrubs, build a water well. Finish by mulching and watering well.

If the plant is balled-and-burlapped, remove fasteners and fold back the top of natural burlap, tucking it down into hole, after you've positioned shrub. Make sure that all burlap is buried so that it won't wick water away from rootball during hot, dry periods. If synthetic burlap, remove if possible. If not possible, cut away or make slits to allow for roots to develop into the new soil. For larger shrubs, build a water well. Finish by mulching and watering well.

If shrub is bare-root, look for a discoloration somewhere near the base; this mark is likely where the soil line was. If soil is too sandy or too clayey, add organic matter. This will help with both drainage and water holding capacity. Fill soil, firming just enough to support shrub. Finish by mulching and watering well.

Problems

Diseases : Rhizactonia Root and Stem Rot

Rhizoctonia is a fungus that is found in most soils and enters the plant through the roots or the stem at soil level. Prevention and Control: First of all, do not overwater and if you suspect Rhizoctonia may be your problem, decrease watering. If a plant is too far gone (all the leaves from the bottom up are wilted), remove it. If your plant is in a container, discard the soil too. Wash the pot with a 1 part bleach to 9 parts water solution. Fungicides can be used, according to label directions. Consult a professional for a legal recommendation of what fungicide to use.

Fungi : Leaf Spots

Leaf spots are caused by fungi or bacteria. Brown or black spots and patches may be either ragged or circular, with a water soaked or yellow-edged appearance. Insects, rain, dirty garden tools, or even people can help its spread.

Prevention and Control: Remove infected leaves when the plant is dry. Leaves that collect around the base of the plant should be raked up and disposed of. Avoid overhead irrigation if possible; water should be directed at soil level. For fungal leaf spots, use a recommended fungicide according to label directions.

Miscellaneous

Conditions : Slope Tolerant

Slope tolerant plants are those that have a fibrous root system and are often plants that prefer good soil drainage. These plants assist in erosion control by stabilizing/holding the soil on slopes intact.

Glossary : Backdrop

Backdrop is the term used to describe a plant or architectural element that is relatively neutral in appearance, that serves as a background for other plants. Backdrop plants are often taller, have dark or medium green leaves, and often of medium texture. However, this is not always the case. For a tropical effect, or to make a space more intimate, use a backdrop with coarse textured foliage. To make a space appear larger, use a small to medium textured leaf plant that is dark green.

Glossary : Deciduous

Deciduous refers to those plants that lose their leaves or needles at the end of the growing season.

Glossary : Small Shrub

A small shrub is less than 3 feet tall.

Plant Images